U.S. Pat. No. 5,265,696 (Casebolt) discloses an example of a prior art fall arrest device that is designed to work in conjunction with a fixed cable on the structure being climbed. The worker wears a safety belt or harness that clips on to the safety device and the device incorporates a friction plate or shoe that grips onto the cable. The user can manually release the friction plate or shoe in order to be able to move up or down relative to the fixed cable.
LeBlanc Ltd. has been in the business of engineering, manufacturing and installing transmission and broadcast towers since 1962. The erection of these structures, with heights up to 2000 feet, requires extensive climbing while working on the tower. What is needed is the development of an effective and efficient fall protection system.
Years ago, LeBlanc was instrumental in the creation of Industry Canada's workplace safety program for work on “aerial transmission towers”. For a long time LeBlanc has instituted and enforced a safety program demanding that all riggers working on towers utilize a fall protection system 100% of the time. This not only applies during construction of the tower, but also in the follow-up servicing and maintenance of the tower, lights, antennas and lines that are an integral aspect of the structure. Because the average tower has a “life expectancy” of over 50 years, there is ongoing maintenance and antenna servicing which will take place on each site.
LeBlanc is the largest tower company in Canada, with offices in 7 regions and over 400 employees, so its interest is in a better fall protection system not only for sale to the marketplace, but primarily for the safety of its own employees.
A fall protection system is what tower climbers (or riggers) count on to be their “life saver” in the event that they slip or lose their balance while working on towers.
In 1998 there was a fatality on a tower where it was later found that the cause of the accident was that the safety device was installed by the rigger “up-side down”. This resulted in the arrest mechanism not being able to engage. Though there had been other accidents where the trolley was installed incorrectly, this was the impetus for a safer and better system.
Though the worker who was killed did not work for LeBlanc, it was felt that with hundreds of riggers using the same fall arrest mechanism as this individual, it was imperative that a system be designed which would better protect LeBlanc's workers.
The fall arrest device disclosed herein is a radical change from previous iterations, and one that has undergone countless tests, including those by The Canadian Standards Association, resulting in its safety accreditation. Among the benefits of this product is that it can not be installed “up-side down”.
The device includes a safety rail which is intended to be fixed to a structure. Slidably mounted on the safety rail is a safety trolley, which connects to the climbers full-body harness. This allows the rigger to climb up and down the structure safely. In the event that the climber slips or transfers their weight to the trolley, the trolley immediately locks onto the rail arresting the fall.
The design profile of the rail features a “T” shape with one side of greater thickness than the other, with the trolley having a mirror profile. This guarantees that the fall arrest feature will always be in the right position. Though seemingly quite simple, this design is the only fall arrest rail system to incorporate this feature.
Among the other benefits of this product is that because or its “ease of operation”, more riggers are apt to use this safety gear. Much like automobile seat belts in their early years, improvements in comfort and ease of operation results in a higher percentage of drivers using the seat belt.
This unique advancement in design is a step forward from previous systems and we would like to consider the development and use of this safety system as proprietary.